Decimal rounding off mechanism



May 10, 1949. c. WITTENMYER 2,469,675

DECIMAL ROUNDING OFF MECHANISM Filed April 20, 1944 FIG.2.

- INVENTOR. CA RLOS WI TTENMYER ATTORNEYS Patented May 10, 1949 UNITEDSTATES PATENT OFFICE 7 Claims.

The present invention relates to calculating machines, and specificallyto automatic means adapted to determine, after a given calculation,whether or not the fractional part of a cent, if any, is five mills ormore, and, if so, to provide for it in the next higher order column.

In common business practice, if a calculation involving fractions,either in numbers of units or prices per unit or both, gives a resultshowing mills, and the number of mills is five or more, it is customaryto follow one of three procedures. One procedure is to add one cent tothe result. Another procedure is to ignore the mills and a thirdprocedure is to alternately add a cent and ignore the mills.

In any of these procedures, transcription of the result of a calculationmay easily produce mistakes due to mistaken reading or failure, in thethird case, to remember when to add and when to ignore.

Among the objects of the present invention is means for eliminating suchpossible mistakes by automatically following a selected one of theprocedures mentioned.

Another object is, as stated above, means for determining, after acalculation, the position of the mills indicator and adding (to make upa cent), ignoring or alternately adding (to make up a cent), andignoring the mills whenever five or less mills is indicated.

A typical calculating machine, such as may have the present deviceapplied to it, is shown in the patent to Neimann, 2,346,601, issuedApril 11, 1944, Calculating machine.

Still other objects and advantages will readily occur to those skilledin the art upon reference to the following description and theaccompanying drawings in which Figure 1 is a diagrammatic view showingthe application of the invention to a single indicator wheel of a keyoperated calculating machine.

Figure 2 is a front elevation of an indicator wheel for use in thepresent invention.

Figure 3 is a side view of a wheel and. part of a casing showing ashutter.

In the drawings, which show in schematic form, means for accomplishingthe results indicated above, the cancelling lever of a calculatingmachine is shown at II]. This acts in the usual fashion to carry out itsfunctions, and, since the present invention is not concerned with suchfunctions and the mechanism used, no such mechanism is being shown.

The lever ID, in the present case, is provided with a segment II whichcarries on its periphery a small hump l2 and preferably a finger I3, theformer being so placed that, at the beginning of the cancelling stroke,it acts upon a, roller l5 carried upon the end of a lever l6 pivoted atH, so as to operate the lever.

narrow part of the wheel and therefore, strike I five or more.

2 Connected to the other end of lever [6, through link 2|! is a block 2|pivoted at 22 and carried upon the block is a pair of spring contacts23. These should be quite flexible and should extend and be adjacent toan indicator wheel 25 such as is shown.

This wheel 25 is the mills wheel and is shown as having a portion of itsrim wider than the rest. The wide portion 25A is so located with respectto the numerals carried by the wheel that such portion is in position tocoact with contacts 23 whenever any of the figures 5 to 9 are visible tothe operator, or are at least in position to be seen.

Therefore, when the block 2| is moved through the action of lever IS,the contacts 23 will be closed whenever the calculation results showfrom five to nine mills, and, if the number of mills is less than five,there is no closing of contacts 23 since they are then opposite thenothing in their downward movement.

Contacts 23 form part of an electric circuit A including a currentsource 26, a suitable switch 21, and a relay 30. This latter is of astandard commercial type having movable contacts adapted to be actuatedby the coil connected in circuit A so as to alternately make and breakthe circuit B with successive completions of circuit A. Each time,therefore, the contacts 23, in their downward movement, strike the wideportion of wheel 25, circuit A is completed (switch 21 being closed) andthe relay opens or closes circuit B.

The circuit B includes a magnet or solenoid 3| a source of current 32,another pair of spring contacts 33, the switch 34, and the contacts inrelay 3!]. When, therefore, this circuit is completed, the magnet 3| isenergized and attracts its armature 36, shown as a bellcrank, and pullsdown the 5-mills key 31 of the machine.

Circuit B is completed, with switch 34 closed, through spring contacts33 and those are moved together at the end of the return stroke of leverHi. This action is accomplished by the finger l3 striking a pivotedweigh-ted member 40 and knocking it upward against the lower one of thecontacts 33.

With the circuits A and B as described, operation of lever iii to cancelthe registration set up in the machine, at the beginning of itsmovement, and before the cancellation is accomplished, moves the feelercontacts 23 downward to find out whether or not the millswheel registersIf such registration exists, the contacts 23 complete the circuit A andchange the relay in circuit B from open to closed, or vice versa,depending upon which it happened to be before moving lever l0.

Assuming the relay to have been open, the

movement of the lever will close it, but nothing will happen since thecontacts 33 are open. The lever in its forward and backward movementthen completes its cancellation. and at the end of its backward stroke,closes contacts 33, momentarily closing circuit B and thereby depressinthe mills key 3'! to set up five in the mills column preparatory for thenext calculation.

So far as the preceding description is concerned, the device willalternately add and ignore the five or more mills on the mills wheel,since the relay 36 is alternately open and closed.

If it is desired always to ignore the mills, it is necessary only toopen switches 2'! and 34. If, on the other hand, it is desired always toadd five mills to the calculation, the relay 39 may be shortcircuited bya shunt 40 controlled by a switch 43. Closing switches 34 and 41 willcause the energization of magnet 31 with each operation of lever ID.

In Figure 3 is shown a means which may be used, if desired, to operatethe switch 21 and provide additional error prevention. In this figure,the machine casing is shown as being provided with a shutter 51 adaptedto open and close the slot or peephole 52 through which the registerwheel 25 is visible. This shutter, when closed will hold togethercontacts 53 acting as switch 21, and therefore may be used to controlcircuit A.

While the wheel 25 is described and shown as having a wide portion tocooperate with the feeler it is obvious that any suitable form of wheelmay be used, provided the feeler can carry out its function ofdetermining whether or not the registered result is five mills or more,or is less than five mills.

While in the foregoing description only one key is mentioned as beingoperated and for a specific purpose, it is obvious that such mechanismsmay be applied to a plurality of keys if desired and other purposes maybe accomplished. The invention is therefore not to be limited to thespecific description but only by the scope of the claims which follow:

I claim:

1. In a calculatin machine having keys and accumulator wheels, a fingermovable to contact a wheel, said wheel having a conformation permittingsuch contact only when in a predetermined position, means for causingsuch finger movement, means for actuating the key corresponding to saidwheel, and means operably connecting the latter means to the fingermovihg means and adapted to cause actuation of the key when said fingercontacts said wheel, said connecting means including means causing suchkey actuation with alternate finger-wheel contacts.

2. In a calculating machine having keys and accumulator wheels, a fingermovable to contact a wheel, said wheel having a conformation permittingsuch contact only when in a predetermined position, means for causingsuch finger movement, an electric switch adapted to be closed when saidfinger and wheel contact and thereby complete a circuit, an alternatingrelay in said circuit, and means for actuating the key corresponding tosaid wheel and including a solenoid for moving said key, said relayadapted to alternately potentially open and close a circuit through saidsolenoid.

3. In a calculating machine having a reset lever, keys and accumulatorwheels, a finger movable to contact a wheel, said wheel havin aconformation permitting such contact only when in a predeterminedposition, means for causing such finger movement, an electric switchadapted to be closed when said finger and wheel contact and therebycomplete a circuit, an alternating relay in said circuit, and means foractuating the key corresponding to said wheel and including a solenoidfor moving said key, said relay adapted to alternately potentially openand close a circuit through said solenoid, and means actuated by saidreset lever to complete the solenoid circuit when potentially closed bysaid relay.

4. In a calculating machine having accumulator wheels for registeringthe result of a calculation and a lever for returning said Wheels tozero position, means for adding predetermined amount when one of saidwheels is in a predetermined result position and means for detectingwhen said wheel is in such position, said operations of detecting andadding being accomplished during the operation of said lever inreturning the Wheels to zero position.

5. In a calculating machine constructed in accordance with claim 1,means for bypassing said alternating means whereby to cause keyactuation whether or not said finger controls said Wheel.

6. In a calculating machine having keys and accumulator wheels, a fingermovable to contact a wheel, said wheel. having a conformation permittingsuch contact only when in a predetermined position, means for causingsuch finger movement, an electric switch adapted to be closed when saidfinger and wheel contact and thereby complete a circuit, an alternatingrelay in said circuit, and means for actuating the key corresponding tosaid Wheel and including a solenoid for moving said key, said relayadapted to alternately potentially open and close a circuit through saidsolenoid, and means to complete the solenoid circuit when potentiallyclosed by said relay:

7. In a calculating machine having keys and accumulator wheels, a fingermovable to contact a wheel, said wheel having a conformation permittingsuch contact only when in a predetermined position, means for causingsuch finger movement, an electric switch adapted to be closed when saidfinger and wheel contact and thereby complete a circuit, an alternatingrelay in saidcircuit, a second circuit, said relay adapted toalternately potentially open and close said second circuit, and means tocomplete the second circuit when potentially closed by said relay.

CARLOS WITTENMYER'.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,046,521 White Dec. 10, 19121,949,706 Barrett Mar. 6, 1934 2,045,437 Daly June 23, 1936 2,149,338Enders Mar. 7. 1939 2,293,127 Fishack et al. Aug. 18, 194-2 2,309,240Chase Jan. 26, 1943 2,343,370 Dickinson Mar. 7, 1944 2,346,601 NiemannApr. 11, 1944

